This invention relates to stop valves commonly used in water supply lines leading to sinks, toilets and the like. A stop valve is simply a shut-off valve to permit replacement of washers or other repairs to be accomplished on a fixture valve without shutting down an entire plumbing system. The stop valve is commonly located in the fixture supply line between the wall and the fixture. Stop valves are generally available in two basic styles. One style is known as an angle stop valve, wherein the inlet and outlet of the valve are at a right angle to each other. The other standard configuration is a straight-through arrangement wherein the inlet and outlet are coaxially aligned with each other.
The most common type of stop valve construction requires about eight or nine separate pieces. The valve body is typically metal and has externally threaded inlet and outlet openings to receive the conventional conduit connections such as a compression ring and compression nut. The valve body also conventionally has a neck portion which is internally threaded to receive the rotatable valve stem and externally threaded to receive the stem-retaining bonnet. The stem has an annular bib washer which is snapped or screwed onto the inner end and which engages the valve seat within the valve body. The stem-retaining bonnet normally has a washer and packer beneath it to seal the neck around the rotatable and axially moveable valve stem. Finally, the operating handle is normally retained to the valve stem by a screw.
The prior art has sought to simplify the construction of the above-described conventional stop valves by eliminating some of the multiplicity of parts. One modified form replaces the externally threaded valve stem and seat-engaging bib washer with a hollow radially resilient rotatable sleeve which has one or more ports in its cylindrical sidewall. In the off or closed position of the sleeve, line pressure enters the sleeve interior and radially expands the resilient cylindrical side walls of the sleeve to prevent water leakage between the exterior of the sleeve and the bore of the valve body. When the sleeve is rotated by a handle to the open position, the side port of the sleeve becomes circumferentially aligned with the outlet bore of the valve body, permitting flow to be established. In the case of an angle stop valve, the valve body inlet bore is coaxial with the sleeve and in continuous communication with the interior of the sleeve. In the straight-through form of the stop valve, the axis of the sleeve is perpendicular to that of the coaxially aligned inlet and outlet bores of the valve body. There are typically two diametrically opposite ports in the sidewall of the sleeve, to selectively communicate with the inlet and outlet bores of the valve body. Representative prior art patents showing resilient sleeve valve constructions are the U.S. Pat. Nos. to Buffet (329,809), Taft (1,160,342), Richter (2,967,042), Eggers (3,353,785), Christiansen (3,529,621), Redman (4,207,732) and Schrock (4,314,581).
It is the principal object of the present invention to improve the resilient sleeve type of stop valves described in the above-listed prior art patents by further simplifying and reducing the number of components to achieve improved economy of manufacture and reliability of operation.